Urinary tract infection (UTI), sometimes also referred to as acute cystitis or bladder infection, is an infection that affects part of the urinary tract. UTI is usually caused by bacteria entering the urinary tract via the urethra. The bacteria can then move upwards through the urinary tract, infecting the bladder (a condition known as cystitis) and sometimes the kidneys (a condition called pyelonephritis). Symptoms of a lower UTI include pain or a burning sensation when passing urine (called dysuria) and/or the feeling of not being able to urinate fully. The patient may also suffer from cloudy, bloody or bad-smelling urine. Lower abdominal pain, mild fever, delirium or acute confusion may also occur.
It is particularly common for older people living in care homes to have bacteria in their urine because their flow of urine is weaker and they are less likely to empty their bladder fully. Urinary tract disorders, such as an enlarged prostate in men or a prolapse in women, may cause bladder emptying problems that may contribute to UTI. Urinary catheters are a common cause of UTI. UTI is the most common hospital acquired infection, accounting for about 23% of all infections, and the majority of these are associated with catheters.
Recurrences are common and if a person has more than two episodes of UTI in three months, this is described as recurrent UTI.
The main causal agent of UTI is Escherichia coli, though other bacteria, viruses or fungi may rarely be the cause.
Traditionally, UTI is treated by antibiotics, although resistance to antibiotics is an increasing problem with regard to UTI. In complicated cases, longer course or intravenous antibiotics may be needed, and if symptoms have not improved in two or three days, further diagnostic testing is needed.
Administration of antibiotics to patients suffering from UTI is not without problems. Firstly, more and more UTI-causing bacterial strains show resistance to the antibiotics traditionally used when treating UTI as mentioned above. Secondly, the antibiotics do not only affect the UTI-causing bacteria but also have side effects in terms of negatively affecting the normal body micro flora.
WO 2009/089442 discloses the usage of a human dietary supplement composition comprising a cranberry derivative or proanthocyanidin-containing concentrate and D-mannose for preventing, controlling and ameliorating UTI caused by E. coli. WO 2011/073112 discloses mannose derivatives useful for the prevention and treatment of bacterial infections, in particular of urinary infections caused by E. coli. 
Research in Microbiology 2011, 162(3): 249-252 investigates the effect of modification of pH on bacterial growth of E. coli ATCC 25922 and Klebsiella oxytoca ATCC 700324 as well as on activity of modern fluoroquinolones in urine in vitro. There was no difference in bacterial growth of E. coli and K. oxytoca observed at pH values between 5.0 and 8.0. However, acidification of urine led to a major impairment of the antimicrobial activity of the tested fluoroquinolones. It was postulated that the reduction in pH impaired uptake of fluoroquinolones into the bacterial cells.
There is still need for an efficient treatment for UTI that is not marred by the problems and shortcomings of traditional antibiotics-based treatment regimens.